1. Field of the Invention
The present invention relates to a color image forming apparatus.
2. Description of the Related Art
Hitherto, a technology in which toner images are successively formed on a surface of a photosensitive member by rotating developing devices that are provided for four colors (yellow, magenta, cyan, and black), and in which the toner images are transferred onto a carrier, such as a transfer material holder or an intermediate transfer member, by successively superimposing them upon each other is known as a technology used in a color image forming apparatus which makes use of an electrophotographic process.
In the color image forming apparatus, since the images of four colors are successively formed by rotating the developing devices so that one color is switched to the next color each time the carrier rotates once, it is necessary to rotate the carrier four times in order to form one full-color image.
Hitherto, in the color image forming apparatus, when density/tone controlling operations (hereinafter simply referred to as “density controlling operations”) are carried out, density control patterns of the corresponding colors are formed. Since, in the density controlling operations, a developing device is switched to another developing device every time the carrier rotates once, the density controlling operations take the time required for the carrier to rotate four times.